A Resonant-Bridge Carrier System for the Measurement of Minute Changes in Capacitance

摘要

A measurement system is described by means of which minute changes in electrical capacitance of the order of 10 to the minus 15th power farads may be resolved to a high degree of accuracy. The over-all principles of operation are discussed and certain circuits and parts of the system are dealt with in detail. Mathematical treatment of important operational characteristics is employed to bring out salient features, particularly as they affect the use and accuracy of the system. Means for operating the gage at some distance from the electronic and recording units of the system are discussed and explained. Several possible applications are suggested by illustration, and schematic wiring diagrams are appended. (Author)